ByRobert R. Bowie, Robert R. Bowie has been concerned with foreign affairs for over 40 years on the Harvard faculty, in government posts, and as a consultant.September 25, 1987

IN itself an agreement to eliminate medium-range and shorter-range nuclear weapons, which now seems likely, will make only a very modest contribution to arms control. It will get rid of one class of weapons; but they amount to under 5 percent of the nuclear arsenals. The Soviets will be giving up four times as many warheads as the United States, but the impact on the balance will be negligible. The agreement will also probably break new ground on verification. Despite the critics, NATO forces will still have a substantial nuclear component; and the US will still be tightly coupled to NATO defense by its 330,000 soldiers in Europe. And the Soviets will still be able to strike European targets using their strategic nuclear weapons.

Yet the agreement can be important. It will revive arms control between the US and Soviet Union after a lapse of eight years. It could lead to agreements on strategic offensive weapons and defense, and on conventional forces.

On the Soviet side, conditions for progress seem propitious. Mikhail Gorbachev appears eager to moderate the military competition and the arms burden while he pursues economic reform. Moreover, Soviet military strategy now seems to be putting more emphasis on modernized conventional forces, and to be reducing reliance on fixed land-based missiles in favor of mobile missiles, and on missile subs, bombers, and cruise missiles.

The issue of strategic offensive weapons is already on the table. Both sides have proposed cuts of 50 percent in such weapons and have now committed themselves to pursue an agreement intensively. Mr. Gorbachev has even talked of achieving one by mid-1988.

That seems very optimistic indeed. Aside from the complexities regarding sublimits, verification, etc., there is the major obstacle of the Strategic Defense Initiative. As a condition for radical cuts in strategic offensive weapons, the Soviets insist on compliance with the Antiballistic Missile (ABM) Treaty as interpreted in 1972, delaying any SDI deployment for 10 years, and agreement on permitted research and testing.

President Reagan remains adamantly opposed. While qualified scientists say a decade of research will be needed to explore the technologies and assess SDI feasibility in order to make informed decisions, the administration is driving to undermine the ABM Treaty and lock the US prematurely into deploying an SDI system.

To clear the way, the administration has reinterpreted the ABM Treaty to gut its restraints on the use of space-based systems based on ``exotic'' technologies. In doing so it has relied on analyses of the treaty by Abraham Sofaer, legal adviser of the State Department, based on legal sophistry and deception. Disregarding the plain terms of the treaty, the ratification record, and the long-accepted interpretation, Mr. Sofaer purported to justify the ``broad'' reading by misleading use of the classified negotiating record. Sen. Sam Nunn demolished this tortured construction by showing that all relevant criteria support the traditional (``narrow'') reading. The Senate Foreign Relations Committee has now issued a report to the same effect. Yet the President and George Shultz have reaffirmed the ``broad'' view.

This rewriting of the treaty shows shocking contempt for both the US Constitution and international law. It blatantly denigrates the Senate's key role in the making of treaties. And it gravely undermines the integrity of US treaty commitments.

Mr. Nunn seems determined to block this cynical effort. But Ronald Reagan can still refuse to make a possible strategic offensive weapons agreement, constraining SDI, even though that need not prevent an orderly SDI research program.

Control of conventional forces is also on the agenda. In April 1986 Gorbachev proposed broad negotiations to cut such forces, and NATO endorsed the idea shortly thereafter. Negotiations are expected to start early in 1988. Their aim should be to reduce the potential for sudden attack and to create a more stable balance at lower force levels.

Progress might be made by first seeking agreement on constraints on deployment and other measures to provide reassurance and increase stability. That might open the way for reducing forces and major equipment. NATO should be working out what sorts of cuts and other steps would enhance its security and confidence of the allies so as to take the initiative in determining how far the Soviets are willing to go toward a more stable balance in Europe.